From d3bacb4600a5ceb2ca34c495815d7988f013c38c Mon Sep 17 00:00:00 2001
From: Vaxry <vaxry@vaxry.net>
Date: Thu, 4 Jul 2024 23:13:23 +0200
Subject: [PATCH] swapchain: add rollback

---
 include/aquamarine/allocator/Swapchain.hpp | 5 +++++
 src/allocator/Swapchain.cpp                | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/include/aquamarine/allocator/Swapchain.hpp b/include/aquamarine/allocator/Swapchain.hpp
index efc7217..3bf2074 100644
--- a/include/aquamarine/allocator/Swapchain.hpp
+++ b/include/aquamarine/allocator/Swapchain.hpp
@@ -24,6 +24,11 @@ namespace Aquamarine {
         Hyprutils::Memory::CSharedPointer<IBuffer>           next(int* age);
         const SSwapchainOptions&                             currentOptions();
 
+        // rolls the buffers back, marking the last consumed as the next valid.
+        // useful if e.g. a commit fails and we don't wanna write to the previous buffer that is
+        // in use.
+        void rollback();
+
       private:
         CSwapchain(Hyprutils::Memory::CSharedPointer<IAllocator> allocator_, Hyprutils::Memory::CSharedPointer<IBackendImplementation> backendImpl_);
 
diff --git a/src/allocator/Swapchain.cpp b/src/allocator/Swapchain.cpp
index f268f92..633d38a 100644
--- a/src/allocator/Swapchain.cpp
+++ b/src/allocator/Swapchain.cpp
@@ -114,3 +114,9 @@ bool Aquamarine::CSwapchain::contains(Hyprutils::Memory::CSharedPointer<IBuffer>
 const SSwapchainOptions& Aquamarine::CSwapchain::currentOptions() {
     return options;
 }
+
+void Aquamarine::CSwapchain::rollback() {
+    lastAcquired--;
+    if (lastAcquired < 0)
+        lastAcquired = options.length - 1;
+}